A frightening new report claims America is “dangerously unprepared” to cope with another terror attack like 9/11.

The report by the Council on Foreign Relations contends the United States needs to spend another $98 billion to brace for an attack – a figure that the federal Department of Homeland Security insisted was “grossly inflated.”

“I believe in the next five years – can’t tell you when, where, what or how – there will be an attack,” former Sen. Warren Rudman (R-N.H.), who chaired the panel that produced the report, told NBC’s “Meet the Press.”

“And God forbid it’s an attack with either chemical or biological or worse, some sort of nuclear device. We are not prepared to deal with that . . . This is a question of protecting the American people from unspeakable horror.”

The report says that in most cities, the police and fire heroes who would be on the front line lack vital equipment like breathing apparatus and even radios. It calls for a national 911 system.

Rudman suggested that better equipment could have avoided “the horrific loss of life of New York firefighters” on Sept. 11, 2001.

The council called for sending more federal preparedness money to probable targets like New York – instead of a “share the spoils” approach that has given Wyoming more money per capita.

The council is a private advocacy group. The director of the report, Jamie Metzl, served in the Clinton White House at the National Security Council and was a Democratic Senate staffer.

“New York is probably one of the best-prepared cities in the United States,” Metzl told The Post. “However, there are still significant gaps that need to be addressed.”

Metzl said one example is difficulties faced by the FDNY, NYPD and other emergency responders in communicating with one another because of problems with their radio systems.

The city and state “can’t do all they need to do without additional support from the federal government,” he said.

The report says that nationally, it isn’t even clear how much states and local governments now spend on homeland security – it could be anywhere from $26 billion to $76 billion on top of $27 billion from the federal government over the next five years.

It also acknowledges that it isn’t clear where the money should be spent, but nevertheless concludes that $98.4 billion more is needed, based on what local agencies reported.

CHART

HELP FOR THE HEROES: To effectively respond to a catastrophic terrorist attack, the U.S. has $98.4B worth of unbudgeted needs.